This invention relates to a centrifugal governor for use with an internal combustion engine, and more particularly to a centrifugal governor of this kind which has a function of increasing the quantity of fuel to be supplied to the engine at the start of same.
A conventional centrifugal governor adapted to increase the fuel supply quantity at the start of the engine is known, e.g. from Japanese Patent Publication No. 58-7814, which comprises a control rack for regulating the quantity of fuel to be supplied to the engine, flyweight members radially displaceable in response to the rotational speed of the engine, a tension lever pivotable about a stationary shaft in response to the radial displacement of the flyweight members, a torque cam having a cam surface determining a fuel increment to be applied at the start of the engine, a sensor lever having one end engaged by the control rack and another end disposed for engagement with the cam surface of the torque cam, the sensor lever being adapted to engage with the cam surface of the torque cam when the engine is in a starting condition, to cause displacement of the control rack inito a fuel increasing positin for the start of the engine, and spring means interposed between the torque cam and the tension lever and urging the torque cam with a force dependent upon the angularity of the tension lever in a direction of disengaging the sensor lever from the cam surface of the torque cam. In the centrifugal governor of this type, the urging force of the spring means is determined by the angularity of the tension lever dependent upon radial displacement of the flyweight members, i.e. the rotational speed of the engine. Therefore, if the engine speed increases while the engine is still in a starting condition requiring increase of the fuel supply quantity, the sensor lever can become disengaged from the torque cam, resulting in interruption of the fuel increasing action. This can degrade the startability of the engine particularly when the engine is started in a low temperature condition.